An electronic device, such as a cellular phone, tablet or an electronic book reader, may include a number of devices to perform different functions. An electronic device may include, for example, a screen for consumption of digital media, such as movies, pictures or electronic books, or a microphone and speaker for participation in a phone call. An electronic device may also include a camera or other image capturing device to allow the user to take and store pictures. Such a camera may include a light emitting device or flash to illuminate the target of the picture.
A light emitting device of such a camera may be used to illuminate the target of the picture uniformly. The uniformity of the light emitting device may be tested during manufacture, prior to installation in the electronic device, and after the electronic device is fully assembled to ensure that the light emitting device emits a uniform field of light.